Month: September 2007

Modern Veblen: Theory Testing

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In 2000, Hal Pashler and I published a paper called “How persuasive is a good fit? A comment on theory testing.” For more than 50 years, psychologists had supported mathematical theories by showing that the equations of the theory could fit data. We pointed out that this was a mistake because no account was taken of the flexibility of the theory. A too-flexible theory can fit anything. However obvious this may sound to outsiders, the practice we criticized was common (and continues).

Recently I asked Hal: Is the problem we pointed out an example of something more general? Neither Hal nor I had a good answer to this. Both of us thought the practice we had criticized was what Feynman called cargo-cult science — looks like science but isn’t — but that was more of a derogatory description than anything else.

Now I think I have a helpful answer: What we pointed out was an example of the general point Thorstein Veblen made in The Theory of the Leisure Class: The growth of worse-than-useless practices among the well-off. Foot-binding. Hood ornaments. Long words and bad writing in scholarly articles. Conspicuous waste. The last chapter of Veblen’s book is about academia.

A Student’s Unlovely View of UC Berkeley (part 2)

Seth Roberts2 Comments

At the Huffington Post, some commentators on my post “A Student’s Unlovely View of UC Berkeley” denounced what they called “coddling”:

That’s Berkeley. No coddling.

Berkeley still is a sink or swim place, with no coddling or significant support system. So what? Grow up.

Coddling? Having your nails done, sleeping on a super-soft bed, being served a fancy dessert — that’s coddling. No one needs coddling, true. But what about basic nutrition? Is being served food with enough Vitamin C coddling? I don’t think so.

The student who spoke to me said that UC Berkeley did nothing to help her find out (a) what she was good at and (b) what she enjoyed. That speaks volumes about UC Berkeley, of course. Students need to learn these things about themselves — everyone does. To go through life without learning these things is a tragedy. It is not asking to be coddled to want these things.

To serve up an education that fails to provide these crucial ingredients is just as unfortunate as a parent or an orphanage serving food that fails to provide essential nutrients. The effect in both cases is the same: Development is stunted. If students weren’t forced to go to schools like Berkeley in order to get a good job (”I’m here for the name” the student told me) it would be less unfortunate. But they are.

Some commentators said Berkeley was somehow better for resembling “the real world” where no one holds your hand. Huh? College students are still growing. Growing things need special environments to grow properly.

One commentator said there are ways to learn on your own: “Go to a library, surf the net, watch TV.” True, there are. But UC Berkeley makes it hard for students to do this because classwork is so time-consuming. Not only does the school serve its students bad food, it makes it hard for them to find good food.

The original post.

Science in Action: Exercise (confirmation)

Seth Roberts3 Comments

During my omega-3 tests, I noticed that exercise seemed to be reducing reaction time (= better brain function). When I tested this, the results surprised me: Reaction time wasn’t lower immediately after exercise but became lower later. Did exercise have a delayed effect or was the shower I took soon after exercise responsible?

To find out, I did a little experiment. The earlier exercise was 30 minutes on a flat treadmill at about 2.8 miles/hour; this time I walked 30 minutes on a steep treadmill at higher speed (about 3.7 miles per hour). Here are the results:

exercise results

Vertical lines show when the exercise started and stopped. This time there was improvement immediately after the exercise (unsurprising, given that it was much more intense) but even more improvement a half-hour later. I took a shower several hours later; it had no clear effect. The improvement lasted several hours before starting to diminish.

The data are very clear. They imply the earlier results can be believed: Exercise does improve brain function in an unanticipated way. Losing weight with exercise is hard; improving brain function with exercise appears easy. I want to study this effect in detail. Not only should it teach me how to improve brain function, it should also suggest the best dose of exercise for the rest of my body.

Loneliness and National Security

Seth Roberts3 Comments

This story — about an NSA employee named Gene Carson — by Igor Vamos is so strange and affecting I would have thought it made up (like Truman Capote’s snakes story) except that almost every detail rings true.

I remember when you used to tell me that fruit from the supermarket is tasteless. I agree with you. If small markets work, why do we need the super markets? I miss you.

This is one of Carson’s diary entries. “You” is Imogene Campbell, whom Carson wiretapped daily but never met.

Given how little I can learn about Gene Carson and Imogene Campbell via Google, maybe it is fiction. If so, Igor Vamos is a genius.

Addendum: I guess it’s fiction.

How Things Begin (Oakland Art Murmur)

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The Oakland Art Murmur is an art-galleries-open-late event that happens the first Friday of every month. It is about a year old. It started when two galleries in a cheap-rent district of Oakland got together. Soon other galleries joined them. There was a meeting at which “nothing happened” (according to a gallery manager) but they got together on paying for advertising and printing. How much did it cost each gallery? I asked. “Not much.”

Each month it has grown larger. More galleries and more people. Recently the City of Oakland began a shuttle bus to take people around and a few galleries now participate that are not close to the original ones. The event has a new name, too: First Fridays Art Night. This is not as weird as it sounds; I learned that there are many First Fridays events at cities all over the country, including Richmond, Virginia, and Washington, DC, but Oakland’s is unusually large — around 40 galleries, whereas in Washington DC there are about 30.

In honor of Freakonomics I visited the Rock Paper Scissors Collective, which turned out to be the most crowded art gallery I have ever seen. People were practically lining up on the street to get in. (Inside was a show of cartoon art and a few racks of clothes.) It felt like every artist in Oakland was there. Across the street was the opening of an exhibit of work by Timothy Brown, which consisted of food or food-related things (such as spoons) in blocks of transparent plastic. I really liked some of it. Upstairs at another gallery a dozen people were finishing a meal. Each person had been given $100 (play money?) which they used to bid for the various dishes.

I learned about the Murmur because a week earlier I had met one of the three founders of The Moon, a nearby art store that opened that night. I was surprised that a senior in college (Mills) is starting a small business, much less an unusual one. At the Murmur I met a woman who had just started a preschool. It was two days old. Craig’s List was involved. She had three partners. “I’m very impressed,” I said. “Most people never start anything.” “You’re starting to walk across the street,” she said.

It was way fun not only because most of the art was quite different than what I see in big-city higher-rent galleries (New Orleans, San Francisco, New York) but also because the people I met were friendly and easy to talk to. Not every conversation went well, however. I saw a guy who sells at the Farmers’ Market. “Are you an artist?” I asked. Yes, he said, but that might be misleading because he was a lot of things. “What else are you?” I asked. He was too tired to answer my question, he said, “but thanks for saying hello.”

Ditto Food: Microwave Popcorn

Seth Roberts1 Comment

In The Shangri-La Diet I argue that the obesity epidemic is due to what I call ditto food: Food that tastes exactly the same each time. Just as you will make a very deep hole with a gun if you hit exactly the same spot each time you fire it, you will produce a very strong flavor-calorie association if you eat a food that tastes exactly the same each time.

The experience of a Colorado man supports this idea. He went to a doctor because of shortness of breath. He didn’t smoke. His test results resembled those of workers in microwave popcorn factories, who often have lung damage because of exposure to a flavoring chemical. The doctor asked the man if he was around a lot of popcorn. “How could you possibly know that about me?” the man said. “I am Mr. Popcorn.” He had eaten microwave popcorn twice a day or more for at least 10 years. When he stopped, he lost 50 pounds in six months. Apparently he made no other changes.

Can Professors Say the Truth? (Michael Bailey and Alice Dreger respond to Joan Roughgarden)

Seth Roberts4 Comments

Michael Bailey and Alice Dreger have responded to Joan Roughgarden’s KQED appearance and her blog post. The NY Times article. Dreger’s paper. Bailey’s book.

In her KQED appearance, Roughgarden said that Bailey’s book was “fraudulent” because it used the word science in its title. Here’s how she said it:

The bottom headline to the cover of Bailey’s book says “The Science of Gender-Bending and Transsexualism.” But in point of fact, there is no science in the book, as they’re apparently now agreeing. And on the whole, the book, as a work of science, is fraudulent.

Dreger notes “by this logic, the publishers of Science Times of the New York Times, the magazine Science News, and thousands of popularizations of science are also guilty of fraud.”

In Pale Fire, the narrator quotes Erich Fromm’s claim that in Little Red Riding Hood, the red hat is a symbol of menstruation. Does Fromm actually believe this? the narrator wonders. Dreger raises a similar question: Does Roughgarden, a professor of biology at Stanford, believe that Science News and the Science Times section are “fraudulent”?

Bailey links to a page with the abstracts of twenty articles by Blanchard related to his typology of transsexuals, which I found very interesting.

Marion Nestle on Omega-3s

Seth Roberts6 Comments

In a January 2007 New York Times article about adding omega-3s to food, Marion Nestle, the NYU nutrition professor, said this:

My experience in nutrition is that single nutrients rarely produce miracles. But it’s also been my experience that companies will put anything in their food if they think the extra marketing hype will help them sell more of it.

I was critical. The single nutrients called vitamins produce miraculous improvements in vitamin-deficiency diseases. In the current issue of Scientific American, Nestle is more accurate:

In the early 1970s Danish investigators observed surprisingly low frequencies of heart disease among indigenous populations in Greenland that typically ate fatty fish, seals and whales. The re­searchers attributed the protective effect to the foods’ content of omega-3 fatty acids. Some subsequent studies—but by no means all—confirm this idea.

Because large, fatty fish are likely to have accumulated methylmercury and other toxins through predation, however, eating them raises questions about the balance between benefits and risks. Understandably, the fish industry is eager to prove that the health benefits of omega-3s outweigh any risks from eating fish. [A mysterious sentence. Perhaps something was lost in the editing.]

Even independent studies on omega-3 fats can be interpreted differently. In 2004 the National Oceanic and Atmospheric Administration—for fish, the agency equivalent to the USDA—asked the Institute of Medicine (IOM) to review studies of the benefits and risks of consuming seafood. The ensuing review of the research on heart disease risk illustrates the challenge such work poses for interpretation.

The IOM’s October 2006 report concluded that eating seafood reduces the risk of heart disease but judged the studies too inconsistent to decide if omega-3 fats were responsible. In contrast, investigators from the Harvard School of Public Health published a much more positive report in the Journal of the American Medical Association that same month. Even modest consumption of fish omega-3s, they stated, would cut coronary deaths by 36 percent and total mortality by 17 percent, meaning that not eating fish would constitute a health risk.

Differences in interpretation explain how distinguished scientists could arrive at such different conclusions after considering the same studies. The two groups, for example, had conflicting views of earlier work published in March 2006 in the British Medical Journal. That study found no overall effect of omega-3s on heart disease risk or mortality, although a subset of the original studies displayed a 14 percent reduction in total mortality that did not reach statistical significance. The IOM team interpreted the “nonsignificant” result as evidence for the need for caution, whereas the Harvard group saw the data as consistent with studies reporting the benefits of omega-3s.

I would have described benefits of omega-3 for which the evidence is clearer, as is done in the cover story about omega-3 in the current issue of Ode. Nabokov called Salvador Dali “Norman Rockwell’s twin brother, kidnapped by gypsies in babyhood.” I think of Ode, which put a Dali lookalike on its July/August 2005 cover, and Spy as linked like that.

Science in Action: Methodology surprise and improvement

Seth Roberts6 Comments

I’ve been using a letter-counting test to keep hour-by-hour track of how well my brain is working. The test consists of 200 trials that ask how many of four displayed letters (e.g., YCAW) are from the set {ABCD}. for YCAW, the answer is 2. Faster answers = better brain function.

For the first several hundred tests, I kept the location of the four letters constant: the center of the window. As soon as I answered, the next display appeared in the same position as the last one. The display never repeated immediately; for example UXRA was never followed by UXRA. But UXRA could be followed by UXAR. This was too easy because it looked like the A and R had switched places. This was a big difference from the usual appearance and it signalled that the answer had not changed. Overlap between one display and the next was probably important but was hard to measure.

To make the test more uniform across trials, I had the display move up and down, which eliminated overlap between one display and the next. Successive displays appeared above center, below center, above center, below center, etc.

To my great surprise, this made the task a lot easier. Here are accuracy scores before and after the change:

accuracy before and after the change

Before the change, mean accuracy was 94.9% (standard error 0.2); after the change, 97.4 (standard error 0.3). The error rate was cut in half, in other words. I had no idea this would happen.

Reaction times were slightly more after the change. A treatment that changes reaction time and accuracy in conceptually opposite directions — makes the task harder in terms of reaction times (= longer reaction times) but easier in terms of accuracy (= great accuracy) — is very unusual. I don’t know of any other examples.

The displays have always been big black letters on a white background — very easy to read. But this change made them seem more visible somehow. At some high level of my visual system, it was if the contrast had been improved. It’s a funny feeling because I thought I was seeing them perfectly clearly with the old procedure.

Because accuracy is better it is now closer to constant, which is what you want in a reaction-time experiment. You want as much variation in reaction time as possible and as little variation in accuracy as possible.